What happens when an electron falls to a lower energy level?

Which represents the correct order of the flow of energy in a food chain?

aev [14]

The answer is c hope this helped

5 0

3 years ago

Dog a is given one cup of food. Dog b is given 1/2 cup of food . Dog.c is given two cups of food at the end of the year dog c we

dusya [7]

Dependent variable: Weight

Independent variable: Amount of food

Explanation:

In experiments such as the one described, there are two or more factors involved, which act as variables. Additionally, these factors can be classified as dependent or independent. The difference between these two is that the independent factor is changed on purpose by the researcher. This occurs with the amount of food as each dog receives a different amount of food and this is controlled by the researcher.

On the other hand, the dependent variable is the main factor analyzed in the experiment or the factor that is modified by the independent variable. In the experiment presented, the dependent variable is weight because in this experiment the focus is to analyze how weight changes with different amounts of food, and this factor is affected by the independent variable.

8 0

3 years ago

Which of the following statements is true

Morgarella [4.7K]

A. you're exposed to nuclear radiation everyday

6 0

4 years ago

Look at the following data provided below:

Vlad1618 [11]

Considering the Hess's Law, the enthalpy change for the reaction is -84.4 kJ.

Hess's Law indicates that the enthalpy change in a chemical reaction will be the same whether it occurs in a single stage or in several stages. That is, the sum of the ∆H of each stage of the reaction will give us a value equal to the ∆H of the reaction when it occurs in a single stage.

<h3>Enthalpy change for the reaction in this case</h3>

In this case you want to calculate the enthalpy change of:

2 C (graphite) + 3 H₂(g) → C₂H₆(g)

which occurs in three stages.

You know the following reactions, with their corresponding enthalpies:

Equation 1: C₂H₆(g) + $\frac{7}{2}$ O₂(g) → 2 CO₂(g) + 3 H₂O(l) ; ΔH° = –1560 kJ

Equation 2: H₂(g) + $\frac{1}{2}$ O₂(g) → H₂O(l) ; ΔH° = –285.8 kJ

Equation 3: C(graphite) + O₂(g) → CO₂(g) ; ΔH° = –393.5 kJ

Because of the way formation reactions are defined, any chemical reaction can be written as a combination of formation reactions, some going forward and some going back.

In this case, first, to obtain the enthalpy of the desired chemical reaction you need 2 moles of C(graphite) on reactant side and it is present in third equation. In this case it is necessary to multiply it by 2 to obtain the necessary amount. Since enthalpy is an extensive property, that is, it depends on the amount of matter present, since the equation is multiply by 2, the variation of enthalpy also.

Now, you need 3 moles of H₂(g) on reactant side and it is present in second equation. In this case it is necessary to multiply it by 3 to obtain the necessary amount and the variation of enthalpy also is multiplied by 3.

Finally, 1 mole of C₂H₆(g) must be a product and is present in the first equation. Since this equation has 1 mole of C₂H₆(g) on the reactant side, it is necessary to locate the C₂H₆(g) on the reactant side (invert it). When an equation is inverted, the sign of delta H also changes.

In summary, you know that three equations with their corresponding enthalpies are:

Equation 1: 2 CO₂(g) + 3 H₂O(l) → C₂H₆(g) + $\frac{7}{2}$ O₂(g); ΔH° = 1560 kJ

Equation 2: 3 H₂(g) + $\frac{3}{2}$ O₂(g) → 3 H₂O(l) ; ΔH° = –857.4 kJ